Vascular streaking and confirmed Verticillium disease among inoculated Norway maple trees.
| 1979 Test | 1980 Test | |
|---|---|---|
| Number of trees: | ||
| total | 46 | 624 |
| vase streaking | 18 | 62 |
| incidence | 39% | 10% |
| Number of diseased trees | ||
| incidence: among all trees | 30% | 8% |
| among trees with | ||
| vascular streaking | 78% | 77% |
| Number of families: | ||
| total | 13 | 40 |
| with diseased trees | 8 | 30 |
| incidence | 62% | 75% |